Immunohistochemical analysis of the development of the structural organisation of chicken spleen

The distribution of T cells, B cells, macrophages and dendritic cells in the chicken spleen was investigated by immunohistochemical staining of cryosections using monoclonal antibodies (MAb) specific for leukocyte (sub)populations. The compartmentalisation of B and T cell zones as peri-ellipsoid (PELS) and periarteriolar lymphoid sheaths (PALS), respectively, and the characteristic distribution of leukocyte (sub)populations in these compartments was evidenced. Special attention was given to the development of structural organisation and lymphoid compartments at the end of embryogenesis and in the neonatal phase. The ontogeny of splenic B cells, T cells and mononuclear phagocytes was examined and is discussed in relationship with the development of immunocompetence. Further, three B cell subpopulations of the spleen, i.e. resting B cells, germinal centre B cells and plasma cells were discriminated based on their expression levels of immunoglobulins, CD57 and Bu-1.status: publishe